Sharing ideas on how to make a more efficent motor using Flyback (MODERATED)

[gotoluc]

Luc, understand this, I build everything I can. I'm not one of those fly-by-night commenters who thinks they know everything. I have experimented with this for some time and have many videos.

Please post the link to your video experiments so we can see your work.

I still don't understand, you say you share for free - yet you still have many secrets.

Have I not shared the above to woopy and anyone else who reads this topic?... I don't appreciate your tone or unfounded accusation.
Let's see what you have shared over the years

regarding the video you show the high voltage coil being used without a CAP, that is a different type of experiment from my question. my question was "Have you been able harness the spike to assist in rotation without a cap then?"

Maybe you need to do the experiment?

Regards

Luc

[woopy]

Hi Luc

Thank's for your encouragement. Very intersting and inspiring video.
I have made a test where it is clear that the flybackspike is really powerfull, as it can spin the rotor quite esaily without the magnetic field of the main motor coil. Very encouraging
.
https://youtu.be/y4S3XvloAnM

Hi Guyla
Thank's for your input. I have made a second video (just above) which will answer a part of your question. Concerning the capacitance, the best rpm i can get with my device as it is is 0.3 uF. Now concerning the impedance of the assistant coil i will see what i can do.


Hi all
Thank's for kind word, and please feel free to replicate

Laurent

[gotoluc]

Thanks again Laurent for this new video demo.

I would suggest that the cap is used to adjust the pulse width (magnetic field on time) of the HV coil. Too much on time can slow the rotor but may prove to have more torque for certain applications and too little on time would not hold the magnetic field long enough to pull or push the rotor magnet or core through.

Thanks for sharing

Luc

[Jimboot]

Thanks Woopy, that was an excellent tutorial & demo. I haven't watched your last one Luc but I have been testing a few of the things you've demonstrated on a couple of motors. I'll be doing a replication tonight and testing various coil configs. Great work guys.

[MileHigh]

Thanks again Laurent for this new video demo.

I would suggest that the cap is used to adjust the pulse width (magnetic field on time) of the HV coil. Too much on time can slow the rotor but may prove to have more torque for certain applications and too little on time would not hold the magnetic field long enough to pull or push the rotor magnet or core through.

I watched Laurent's video and there were some interesting things revealed.

However, for starters, I think Laurent made some mistakes.  He needed longer wires connected to the main drive coil so that he could move it much farther away from the rotor when he wanted to eliminate the influence of the main drive coil on the spinning rotor.  Perhaps adding another 30 cm of wire would have allowed him to move the main drive coil a safe distance away from the rotor.  The second issue is that I don't think he gave the rotor enough time spin down and stabilize at a new RPM after the main drive coil was partially removed from influencing the rotor.  It's a hard drive bearing motor, so perhaps waiting at least 45 seconds to a minute would be required to let the rotor stabilize at a new speed when only being driven by the high-voltage coil.

You can clearly see a trend in Laurent's clip with respect to the changing of the capacitor:  If you increase the value of the capacitor the maximum voltage decreases and the discharge time increases.  Likewise if you decrease the value of the capacitor the maximum voltage increases and the discharge time decreases.

Now, if your goal is to get the highest RPM for your rotor, that suggests you want to have the high-voltage coil switched ON so the rotor magnet gets a push from one pole and a pull from the other pole of the high-voltage coil.  You want the high-voltage coil to switch OFF at the end of the pull phase.  This is a function of the ON time, the angle subtended by the two poles of the high-voltage coil, and the RPM of the rotor when it stabilizes at maximum speed.

One more time, this all is an investigation into the timing analysis of the motor.  It's hard to find that "Goldilocks" timing with fixed components, but nothing is stopping you from playing with the value of the capacitor live while the motor is running.  What you do need though is an accurate timing reference.  The easiest way to do that would be to use a small independent pick-up coil to sense the rotor magnet fly-bys and trigger on that.  You "sacrifice" a scope channel for that but then you are not "flying blind."  You can use your second scope channel to look at other events and know exactly what the rotor position is relative to those other events.  Timing is everything when it comes to a pulse motor.

Another option if you are hard core is to look at TK's MHOP clips and make an "LED strobe-scope" or "LED timing gun" and look at the rotor spinning in dim light with the LED illumination revealing the timing to you.